在 ForEach-Object -Parallel 块内从自身递归调用函数 - 并行块内无法识别函数

第一次在这里提问。请善待:)

我试图以并行方式递归地获取所有目录，希望减少遍历驱动器所需的时间。下面是我尝试过的代码。本质上我想要做的是输入一个文件夹，并对其子文件夹及其子文件夹等并行执行相同的操作，但该函数在并行块内无法识别

function New-RecursiveDirectoryList {
    [CmdletBinding()]
    param (
        # Specifies a path to one or more locations.
        [Parameter(Mandatory = $true,
            Position = 0,
            ValueFromPipeline = $true,
            ValueFromPipelineByPropertyName = $true,
            HelpMessage = 'Path to one or more locations.')]
        [Alias('PSPath')]
        [ValidateNotNullOrEmpty()]
        [string[]]
        $Path
    )
    process {
        foreach ($aPath in $Path) {
            Get-Item $aPath

            Get-ChildItem -Path $aPath -Directory |
                # Recursively call itself in Parallel block not working
                # Getting error "The term 'New-RecursiveDirectoryList' is not recognized as a name of a cmdlet"
                # Without -Parallel switch this works as expected
                ForEach-Object -Parallel {
                    $_ | New-RecursiveDirectoryList
                }
        }
    }
}

Error:

New-RecursiveDirectoryList: 
Line |
   2 |                      $_ | New-RecursiveDirectoryList
     |                           ~~~~~~~~~~~~~~~~~~~~~~~~~~
     | The term 'New-RecursiveDirectoryList' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

我还尝试使用 mklement0 提供的解决方案here但没有运气。以下是我对此的尝试：

    function CustomFunction {
    [CmdletBinding()]
    param (
        # Specifies a path to one or more locations.
        [Parameter(Mandatory = $true,
            Position = 0,
            ValueFromPipeline = $true,
            ValueFromPipelineByPropertyName = $true,
            HelpMessage = 'Path to one or more locations.')]
        [Alias('PSPath')]
        [ValidateNotNullOrEmpty()]
        [string[]]
        $Path
    )

    begin {
        # Get the function's definition *as a string*
        $funcDef = $function:CustomFunction.ToString()
    }

    process {
        foreach ($aPath in $Path) {
            Get-Item $aPath

            Get-ChildItem -Path $aPath -Directory |
                # Recursively call itself in Parallel block not working
                # Getting error "The term 'New-RecursiveDirectoryList' is not recognized as a name of a cmdlet"
                # Without -Parallel switch this works as expected
                ForEach-Object -Parallel {
                    $function:CustomFunction = $using:funcDef
                    $_ | CustomFuction
                }
        }
    }
}

Error

CustomFuction: 
Line |
   3 |                      $_ | CustomFuction
     |                           ~~~~~~~~~~~~~
     | The term 'CustomFuction' is not recognized as a name of a cmdlet, function, script file, or executable program.
Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

有谁知道如何实现这一点或以不同的方式实现这一点？

所以，这对我有用，但显然看起来不太漂亮。 需要注意的一件事是，foreach ($aPath in $Path) {...}在你的脚本上是不必要的，process {...}当您通过多个路径时，块会为您处理这个问题。

Code:

function Test {
    [CmdletBinding()]
    param (
        # Specifies a path to one or more locations.
        [Parameter(
            Mandatory,
            ParameterSetName = 'LiteralPath',
            ValueFromPipelineByPropertyName,
            Position = 0)]
        [Alias('PSPath')]
        [string[]] $LiteralPath
    )

    begin {
        $scriptblock = $MyInvocation.MyCommand.ScriptBlock.ToString()
    }

    process {
        # Get-Item $Path <= This will slow down the script
        $LiteralPath | Get-ChildItem -Directory | ForEach-Object -Parallel {
            $sb = $using:scriptblock
            $def = [scriptblock]::Create($sb)
            $_ # You can do this instead
            $_ | & $def
        }
    }
}

回顾这个答案，我今天建议的是不要使用递归并使用ConcurrentStack<T>相反，这会提高效率并消耗更少的内存。还值得注意的是，如马克门0在他的评论中指出，您的代码一开始是正确的，问题是由于拼写错误造成的：$_ | CustomFuction -> $_ | CustomFunction.

function Test {
    [CmdletBinding()]
    param (
        [Parameter(
            Mandatory,
            ParameterSetName = 'LiteralPath',
            ValueFromPipelineByPropertyName,
            Position = 0)]
        [Alias('PSPath')]
        [string[]] $LiteralPath,

        [Parameter()]
        [ValidateRange(1, 64)]
        [int] $ThrottleLimit = 5
    )

    begin {
        $stack = [System.Collections.Concurrent.ConcurrentStack[System.IO.DirectoryInfo]]::new()
        $dir = $null
    }

    process {
        $stack.PushRange($LiteralPath)
        while ($stack.TryPop([ref] $dir)) {
            $dir | Get-ChildItem -Directory | ForEach-Object -Parallel {
                $stack = $using:stack
                $stack.Push($_)
                $_
            } -ThrottleLimit $ThrottleLimit
        }
    }
}